HP XP Racks User Manual
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3.
On the primary storage system, run the Pairsplit-S RAID Manager command on the P-VOL
to release the ESAM pair.
4.
Clear the failure in the primary storage system P-VOL.
5.
On the secondary storage system, create a Continuous Access Synchronous pair from the
original S-VOL to the P-VOL. Data flow is from the secondary to primary storage systems.
6.
Continue by either changing the Continuous Access Synchronous pair to a ESAM pair (below)
or recreating the ESAM pair (next steps).
If changing the Continuous Access Synchronous pair to a ESAM pair, complete this step. If
using RWC, go directly to the RWC step.
1.
On the primary storage system, run the RAID Manager horctakeover command on
the new Continuous Access Synchronous S-VOL. This reverses the relationship of the pair.
2.
On the primary storage system, split the Continuous Access Synchronous pair using the
Pairsplit-r dialog box.
3.
On the primary storage system, use RWC’s Pairresync dialog box to change the
Continuous Access Synchronous pair to a ESAM pair. For more information, see
“Changing Continuous Access Synchronous pairs to ESAM pairs ” (page 39)
7.
If recreating the ESAM pair using RAID Manager:
1.
On the secondary storage system, when the copy operation is completed, run the following
command to release the Continuous Access Synchronous pair:
pairsplit -S
2.
On the primary storage system, run the following command to create the ESAM pair:
paircreate
8.
If recreating the ESAM pair using RWC:
1.
On the secondary storage system, release the Continuous Access Synchronous pair.
2.
On the primary storage system, create the ESAM pair.
9.
On the primary and secondary storage systems, make sure that Type shows ESAM.
10. Using multipath software, vary the owner path online.
11. Restart I/O.
Recovering from secondary volume failure on the MCU
When this failure occurs, automatic system failover switches host I/O to the primary volume on
the RCU. Recovering the volume from this failure involves releasing the pair, clearing the failure,
recreating the pair, restoring the original relationship of the volumes, and restoring normal host
I/O.
NOTE:
If the failed volume is an external volume, contact the HP Support Center for assistance
clearing the failure.
You use multipath software and either RWC or RAID Manager to complete the recovery procedure.
TIP:
Some of the steps can be done using either RWC or RAID Manager. Typically, these steps
can be completed more quickly using RAID Manager.
1.
Using multipath software, make sure that the secondary storage system is receiving I/O.
2.
Stop I/O from the host.
3.
On the secondary storage system, release the ESAM pair by running the following RAID
Manager command on the P-VOL:
Pairsplit-S
4.
Clear the failure in the primary storage system P-VOL.
Recovery from blocked pair volumes
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